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Ubuntu 9.04 Daily Build Boots In 21.4 Seconds
Pizzutz writes "Softpedia reports that Ubuntu 9.04 Boots in 21.4 Seconds using the current daily build and the newly supported EXT4 file system. From the article: 'There are only two days left until the third Alpha version of the upcoming Ubuntu 9.04 (Jaunty Jackalope) will be available
(for testing), and... we couldn't resist the temptation to take the current daily build for a test drive, before our usual screenshot tour, and taste the "sweetness" of that evolutionary EXT4 Linux filesystem. Announced on Christmas Eve, the EXT4 filesystem is now declared stable and it is distributed with version 2.6.28 of the Linux kernel and later. However, the good news is that the EXT4 filesystem was implemented in the upcoming Ubuntu 9.04 Alpha 3 a couple of days ago and it will be available in the Ubuntu Installer, if you choose manual partitioning.' I guess it's finally time to reformat my /home partition..."
boots 3.1 seconds faster with ext4 over ext3
So in order to be a "visionary", I merely have to decide what consumers might want (not that hard being one yourself), and then ask people smarter than yourself to make it happen with no actual technical insight on how to make it happen yourself?
Sorry to break it for you but boot time is measured from the push of the power button to a usable desktop.
You may enjoy your 26 seconds of pretending that "this is not really happening" - most other people don't.
Why does it take so long to discover those drives and other devices? Why does a CD-ROM drive take hundreds of milliseconds to be recognized during a POST? These things should happen basically instantly at modern hardware speeds, and yet they don't.
It reminds me of NFS timeouts. Years ago when I worked in an environment where everyone NFS mounted a shared filesystem, there would occasionally be outages on the server or in the network. My local system would lock up and hang for MINUTES while it timed out on requests to the NFS server. I could never understand why the thing didn't just time out in seconds rather than minutes. Even at that time, we were running 10 MBit or maybe 100 MBit network connections; if the remote system is going to respond, it's going to happen at MOST after a few second delay. Waiting for minutes just seems dumb.
The same sort of thing happens alot with web browsers too that wait far too long for servers to time out. If the server doesn't respond in 10 seconds, it's not going to respond. Ever. There's no reason to wait 30 seconds or longer to timeout an HTTP connection ...
You know how everyone wanted a Linux-based operating system that "just worked" on a wide variety of hardware with drivers for everything? And didn't throw a shit-fit if you moved the hard disk to a completely different machine and tried to boot it up?
That's why Linux takes so long to boot these days. You can have very good hardware compatibility or you can have very good boot speed. You can't have both. (Well, until someone invents persistent RAM.)
The CD-ROM does respond to the BIOS very quickly. What takes forever is the BIOS checking each controller, chain, and bus location for a device. Waiting for those probes to time out is what takes so long. This isn't just the BIOS either, it's the Linux kernel too and any OS that might want to speak to whatever hardware might happen to be there.
Seems dumb to you, the user. Didn't seem dumb to the programmers who wrote NFS and whatever application you were using. Why? NFS is 1) a block device, and 2) largely a hack. The way UNIX was designed, block devices just don't disappear from the system. Just like wheels (ideally) don't go flying off your car while you're driving down the road. But when NFS, a block device can suddenly go unavailable and as far as the OS is concerned, that's just really really bad for all sorts of reasons. The programmers figured that in order to make the system as robust as possible, they'd extend the timeout as long as tolerable to reduce the chances of data loss and corruption as much as possible. It's conceivable that a large number of problems could be resolved in a matter minutes (say, somebody tripped over the power cord for the network switch), thus preventing the loss of what could be very valuable data.
You click a mouse button. This initiates a request which, after all of the appropriate nameservers have been consulted, hops from your machine over dozens of routers, switches, and cables owned by different countries and corporations. It travels thousands of miles away to some place you can't even pronounce. Once there, the server recognises the request and acts on it, sending you back a mix of static content, images, and database content several orders of magnitude greater in size than your original request. The content then travels back to you another few thousand miles, perhaps via a different path until it eventually reaches your machine where it is processed and displayed in a mostly-legible fashion. And you have the gall to complain that sometimes it takes longer than 10 seconds for all of this to happen?
Good. Fucking. Grief.
I'm continually amazed that it works at all and I'm a sysadmin at a web hosting company. Almost every day I run across a site I want to visit that takes longer than 10 seconds to respond in full. There are lots of very good reasons that a website might take between 10-30 seconds to load in your browser. The authors of the HTTP protocol, web server software, and web browsers having a personal grudge against you sure isn't one of them.